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基于刚性运动网格和动态拼接网格的两种非定常计算网格策略,对NREL Phase VI风力机非定常塔影效应开展数值模拟研究.流动控制方程选取雷诺平均N-S方程,时间求解应用“双时间步”离散求解,湍流模型为单方程SA模型.通过对有/无塔架流动情况进行模拟,发现有/无塔架两种状态得到的叶片各站位压力系数分布与试验值基本吻合,表明采用的非定常计算方法是可行的;有塔架下叶片相位角Φ=90°状态的前缘吸力峰较相位角Φ=270°偏低;有塔架相位角Φ = 270°附近流场结构简单,而相位角Φ = 90°附近流动受塔架干扰明显.在此基础上,分析有塔架下单个叶片推力与扭矩随相位角的变化曲线,发现扭矩与推力均存在随相位角变化的两种波动现象,表现为大“凹坑”与小幅抖动的特征.进一步的分析表明,载荷“凹坑”由风力机塔架引起,而载荷小幅抖动由叶根过渡区的流动分离引起.叶片载荷随相位角变化特性机理的阐明对于风力机叶片动态载荷设计具有一定工程价值.“,”Basing on the dynamic grids, the unsteady tower shadow effect of NREL Phase VI wind turbine was studied with N-S equation as the governing equation, dual-time as the solution and SA model as the turbulence model. The feasibility of unsteady methods employing dynamic crossed-grid and dynamic patched-grid were verified by calculation, comparison and analysis. Furthermore, impact assessment with/without tower is as follows: pressure distributions on blade with and without tower are both approximate to experimental data. the leading edge of blade at 90° azimuthal angle with tower will have a lower suction peak than that at 270° azimuthal angle. Blade at 270° azimuthal angle with tower will have a simpler flow field structure while blade at 90° azimuthal angle will be interfered obviously by the flow near tower. Meanwhile, there are two kinds of fluctuations that load pit and slight load fluctuation for single period blade's thrust and torque curve with azimuthal angle changes, and the load pit is caused by the wind turbine tower, and the slight load fluctuation is caused by the flow separation at the root of blade. The study of blade load changes has certain value for dynamic load design of wind turbine blade.